The company’s Alexa Fund, which it usually uses to fund voice-technology ventures, has invested in prefabricated housing startup Plant Prefab, the startup announced on Tuesday. Plant Prefab focuses on building new, prefabricated, single- and multi-family homes using sustainable practices, and it claims it can build faster and with less waste than traditional methods, according to the company’s website.

Obvious Ventures also participated in the startup’s $US6.7 million round of funding.

Why is Amazon’s Alexa Fund interested in a prefab home startup? It’s just the latest move that suggests that Amazon’s Alexa technology is all about the home.

“Voice has emerged as a delightful technology in the home, and there are now more than 20,000 Alexa-compatible smart home devices from 3,500 different brands,” Paul Bernard, director of Amazon’s Alexa Fund, said in a prepared statement.

“Plant Prefab is a leader in home design and an emerging, innovative player in home manufacturing. We’re thrilled to support them as they make sustainable, connected homes more accessible to customers and developers.”

Bernard refers directly to connected homes, an area that could spell growth for Amazon if the company is able to integrate Alexa into a home before it is even built and delivered to customers.